AFGHANISTAN - Lucky Shot, "Blackhawk Down"

"Deadly 'Lucky Shot' on Helicopter Unlikely to Change U.S. Tactics in Afghanistan"
PBS Newshour 8/8/2011

COMMENT: I have experience with military helicopters, Navy with HSL-33. Helicopters are easy to soot down because they hover AND how they stay airborne. Any damage to the helicopter's blades (tail or main) will cause an imbalance and likely bring it down, so you don't have to hit the fuselage. In the above story, an RPG was used while the helo was in a hover approach-landing.

I don't know if it was true, but when I was on the USS Hancock (with a squadron VF-211) off North Viet Nam, I heard that a helo was brought down by a shot from a crossbow. "Charley" used crossbows for silent kills.